"Developing better methods for the sustainability assessment of seafood"

Kristina Bergman has started her PhD by mapping the knowledge gaps in Swedish seafood production and sustainability. Now her goal is to increase knowledge about biodiversity in particular, in order to help guide the Swedish seafood sector in an increasingly sustainable direction.

Before being accepted as a Blue Food doctoral student at KTH, Kristina Bergman had already worked with seafood and sustainability at the research institute Rise for six years, where she had several colleagues who are also active in Blue Food. As a newly accepted doctoral student, she nevertheless chose to start from scratch with a survey of what research has already been done and what has not been done when it comes to seafood and sustainability. Meetings with Blue Food partners such as WWF, MSC, ASC, Ica and Coop have led to the realization that one area where there is a large lack of scientific data is biodiversity.

Better decision-making with more perspectives

Kristina Bergman has previously worked mainly with life cycle assessments. In this field, there are good methods to guide in areas such as climate impact, acidification and land and water use. But biodiversity is an aspect for which there is a lack of methods. By focusing on it, she wants to contribute to better evaluations of seafood products, such as new types of seafood or production methods.

It is inspiring how, for example, WWF's meat guide and Coop's sustainability declarations take into account a number of sustainability aspects. In the past, there have mainly been methods for evaluating climate impact, but failing to consider biodiversity, for example, risks steering producers and consumers in a less environmentally sustainable direction.

BIld of woman in polka dot shirt
Kristina Bergman, KTH

Kristina Bergman's real ambition is to combine biological, economic and social sustainability. But to make the work manageable, she has chosen to focus primarily on biological sustainability. However, something that is close to her heart and that she wants to work on is combining the environmental perspective with health and consumption, which is part of social sustainability.

From a combined perspective, for example, herring and mackerel - which have good health, price and sustainability values - score well, while eel, while containing substances that are good for health, scores poorly in terms of sustainability. Another example is shrimp, which requires large amounts of diesel when fished and is not very healthy, but is still a popular seafood. In Sweden, fishing quotas for shrimp and shrimp trawlers are also smaller than in neighboring countries, which means that profitability is lower. Therefore, the sharp increase in the price of diesel has led to a significant reduction in shrimp fishing in Sweden in the spring of 2022.

Algae, meetings and collaboration

Woman by the sea holding seaweed
Kristina Bergman in Roscoff, France

In addition to participating in doctoral courses and working on the structure of her doctoral project, Kristina Bergman has taken several concrete steps in her research career. Among other things, she has initiated a collaboration with a researcher at the University of Shanghai on sustainability evaluation of algae cultivation in China. The evaluations made so far have been based on relatively small-scale European farms, but the absolute majority of all algae cultivation is in Asia, with much larger farms. Her goal with the collaboration is to find out the environmental advantages and disadvantages of large-scale cultivation and how it could be applied in Sweden.

In spring 2022, Kristina Bergman also published an article on environmental assessment of algae, building on her previous work. It addresses the concept of an algae biorefinery that can be used to produce things like alginate, packaging materials and biogas. She has also had the opportunity to visit the biological research station at Roscoff in Brittany, France, and made contacts with other researchers, particularly in the field of algae production.

So far, algae have been the main focus of her work, but in the future she plans to work on salmon and mussels. Later this year, she also plans to give a presentation at a conference on life cycle assessment in Peru, not least to learn about the latest findings on sustainability.

Kristina Bergman's project is largely theoretical, but she is keen for it to produce results that can be used in practice.

I hope that my research can inform the decision-making of large retailers, which is probably a more viable option than trying to influence consumers directly. My PhD colleague Elena Costa and I have been talking about how to package sustainability information to best effect change. I'm really looking forward to working with Elena to best package and disseminate my research.

The young researchers in Blue Food are in close contact and there are good opportunities for exchange between them. In addition to a continued collaboration with Elena Costa, she already has thoughts about future collaboration with Pontus Gunnarsson, SLU and KTH colleague Evangelia Zioga.

The project is particularly relevant to research area 5. Sustainability analysis

Kristina Bergman's project is expected to be completed in autumn 2025.

Principal supervisor

Fredrik Gröndahl, KTH

Assistant supervisor

Linus Hasselström, KTH
Sara Hornborg, RISE
Anders Högberg, Orkla
Åsa Strand, IVL
Jean-Baptiste Thomas, KTH.

Kristina Bergman's profile page on KTH's website


"Environmental and biodiversity performance of a novel single cell protein for rainbow trout feed", Science of The Total Environment, volume 907, 10 January 2024. Kristina Bergman, Markus Langeland.

"Life Cycle Assessment of a large commercial kelp farm in Shandong, China", Science of The Total Environment, volume 903, 10 December 2023. Kristina Bergman, Fredrik Gröndahl.